I just ran across this article over at Popular Mechanics on the pros and cons of fuels such as ethanol (HT to Instapundit). I've only read the first page so far. But here's a nice paragraph:
In the lab, many gasoline alternatives look good. Out on the road, automotive engineers have a lot of work to do, and energy companies have new infrastructure to build, before very many people can drive off into a petroleum-free future. And, there's the issue of money. Too often, discussions of alternative energy take place in an alternative universe where prices do not matter.